My guess would be the tree will be fine. You'll know come spring and leaf out. You might write a letter detailing the damage to the installer to allow you to claim costs if you have to take the tree down, but most big, old trees survive a lot of damage. I have a maple too close to the road that gets damaged by snow plows not infrequently. It's fine.

You're unlikely to need the valve, so I'd just plant around it. Something like hostas will hide it completely. You'll want to save a photo to tell you where it is, so you can find it again once it's covered with leaves.

Thank you for your thoughtful reply. I am on the right track because I thought Hostas would work well too! The plumber told us up front that the oak roots had grown into the old original sewer line and he wasn’t sure how much damage he would cause pulling out the damaged pipe and roots, but he would try to do minimal damage.